The greatest competitor in the history of “The Challenge” ain’t playin’ real football anytime soon … ’cause the dude was straight-up ROCKED by the NFL’s Maurkice and Mike Pouncey on Thursday!!

Unclear why Johnny Bananas was in Boca Raton, Florida training with NFLers Mark Ingram, Carl Lawson and the Pouncey twins … but, the MTV show’s star openly accepted the invitation for the beatdown when it all went down.

Egged on by Ingram … Bananas tried pass rushing on the Pounceys — who are anchors on the Steelers’ and Chargers’ O-lines — and the reps didn’t go well for Johnny.

J.B. was thrown to the turf a couple times … and, at one point — he was run from the field to the wall by Mike!!